You MIGHT be able to get it done leaving the shaft in. Take your wheel off, take the drum off, beat the old broke portion out of the wheel flange. If you can fit the new wheel stud through between the wheel flange and the drum components, simply start it in the hole, grab some washers, then take an impact gun to a lugnut(or a nut that threads onto the stud) and tighten it up against itself.
If it won't fit, time to pull a shaft. I prefer the taking the shaft out myself...makes it easier for me and no possible hard bangs against the c-clip. Plus, gives you a chance to change rear fluid and check out your center pin in the differential as well as the spiders and the ring and pinion. I use a deep socket to space the studs off the ground, then beat it through the backside of the wheel flange.
'01 XLT disguised as a '03 Fx4 Level II.